The invention discloses a preparation method of a high-entropy alloy CoCrCuFeNi laser recasting layer. The preparation method comprises the following steps that 1, a high-entropy alloy CoCrCuFeNi rawmaterial is prepared, and the raw material is put into a water-cooled copper crucible; 2, the vacuum degree is vacuumized to 5*10 Pa, an air suction system is closed, argon is injected, the air inflation system is closed; 3, arc striking is started, so that the metal raw material is completely molten; 4, after different metal elements are uniformly fused, so that the metal elements naturally coolthe metal raw material in a circulating water cooling copper mold, and a round cake-shaped ingot is finally obtained; 5, the smelted high-entropy alloy CoCrCuFeNi round cake-shaped ingot is cut into asheet through a wire cutting method; and 6, a continuous multi-channel laser remelting method is adopted to weld the surface of the high-entropy alloy CoCrCuFeNi: the yield stress of the high-entropyalloy CoCrCuFeNi laser remelting layer is calculated, wherein the yield stress of the laser remelting layer is larger than that of a base material, the yield stress of the base material is 125.94 +/-23.56 MPa, the laser power is 500 W, the welding speed is 1.4m/min, and the yield stress of the laser remelting layer obtained under welding parameters is the maximum and reaches 306.06 +/-31.49 MPa.